public class FileImageInputStream extends ImageInputStreamImpl
ImageInputStream that gets its input from a
File or
RandomAccessFile. The file contents are assumed to be stable during the lifetime of the object.
bitOffset, byteOrder, flushedPos, streamPos| Constructor and Description |
|---|
FileImageInputStream(File
Constructs a
FileImageInputStream that will read from a given
File.
|
FileImageInputStream(RandomAccessFile
Constructs a
FileImageInputStream that will read from a given
RandomAccessFile.
|
| Modifier and Type | Method and Description |
|---|---|
void |
close()
Closes the stream.
|
protected void |
finalize()
Finalizes this object prior to garbage collection.
|
long |
length()
Returns the length of the underlying file, or
-1 if it is unknown.
|
int |
read()
Reads a single byte from the stream and returns it as an
int between 0 and 255.
|
int |
read(byte[] b, int off, int len)
Reads up to
len bytes from the stream, and stores them into
b starting at index
off.
|
void |
seek(long pos)
Sets the current stream position to the desired location.
|
checkClosed, flush, flushBefore, getBitOffset, getByteOrder, getFlushedPosition, getStreamPosition, isCached, isCachedFile, isCachedMemory, mark, read, readBit, readBits, readBoolean, readByte, readBytes, readChar, readDouble, readFloat, readFully, readFully, readFully, readFully, readFully, readFully, readFully, readFully, readInt, readLine, readLong, readShort, readUnsignedByte, readUnsignedInt, readUnsignedShort, readUTF, reset, setBitOffset, setByteOrder, skipBytes, skipBytespublic FileImageInputStream(Filef) throws FileNotFoundException , IOException
FileImageInputStream that will read from a given
File.
The file contents must not change between the time this object is constructed and the time of the last call to a read method.
f - a
File to read from.
IllegalArgumentException - if
f is
null.
SecurityException - if a security manager exists and does not allow read access to the file.
FileNotFoundException - if
f is a directory or cannot be opened for reading for any other reason.
IOException - if an I/O error occurs.
public FileImageInputStream(RandomAccessFileraf)
FileImageInputStream that will read from a given
RandomAccessFile.
The file contents must not change between the time this object is constructed and the time of the last call to a read method.
raf - a
RandomAccessFile to read from.
IllegalArgumentException - if
raf is
null.
public int read()
throws IOException
ImageInputStreamImpl
int between 0 and 255. If EOF is reached,
-1 is returned.
Subclasses must provide an implementation for this method. The subclass implementation should update the stream position before exiting.
The bit offset within the stream must be reset to zero before the read occurs.
read in interface
ImageInputStream
read in class
ImageInputStreamImpl
-1 if EOF is reached.
IOException - if the stream has been closed.
public int read(byte[] b,
int off,
int len)
throws IOException
ImageInputStreamImpl
len bytes from the stream, and stores them into
b starting at index
off. If no bytes can be read because the end of the stream has been reached,
-1 is returned.
The bit offset within the stream must be reset to zero before the read occurs.
Subclasses must provide an implementation for this method. The subclass implementation should update the stream position before exiting.
read in interface
ImageInputStream
read in class
ImageInputStreamImpl
b - an array of bytes to be written to.
off - the starting position within
b to write to.
len - the maximum number of bytes to read.
-1 to indicate EOF.
IOException - if an I/O error occurs.
public long length()
-1 if it is unknown.
length in interface
ImageInputStream
length in class
ImageInputStreamImpl
long, or
-1.
public void seek(long pos)
throws IOException
ImageInputStream
An IndexOutOfBoundsException will be thrown if pos is smaller than the flushed position (as returned by getflushedPosition).
It is legal to seek past the end of the file; an java.io.EOFException will be thrown only if a read is performed.
seek in interface
ImageInputStream
seek in class
ImageInputStreamImpl
pos - a
long containing the desired file pointer position.
IOException - if any other I/O error occurs.
public void close()
throws IOException
ImageInputStream
IOExceptions or incorrect behavior. Calling this method may allow classes implementing this interface to release resources associated with the stream such as memory, disk space, or file descriptors.
close in interface
Closeable
close in interface
AutoCloseable
close in interface
ImageInputStream
close in class
ImageInputStreamImpl
IOException - if an I/O error occurs.
protected void finalize()
throws Throwable
close method is called to close any open input source. This method should not be called from application code.
finalize in class
ImageInputStreamImpl
Throwable - if an error occurs during superclass finalization.
WeakReference,
PhantomReference